The invention relates to a Mecanum wheel for omnidirectional driving manoeuvres without mechanical steering, having a first rim carrying rollers arranged in a circumferential direction next to one another which are rotatably mounted about a roller axis of rotation that is arranged at an angle to a first rim axis of rotation. In other words, the rollers are rotatable about roller axes of rotation which are arranged at an angle to the first rim axis of rotation. Furthermore, the invention relates to a vehicle having a plurality of such Mecanum wheels.
Mecanum wheels are generally known. On the circumference of the rim of the wheel, multiple rotatably mounted rollers which as a rule are barrel-shaped are rotatably attached mostly at an angle of 45° to the axis of the rim and thus of the wheel. It is not the rim but exclusively the aforementioned rollers that establish contact with the ground. The rollers have no direct drive and can freely rotate about their respective roller axis of rotation. The entire Mecanum wheel by contrast can be driven by a drive motor with variable direction of rotation and variable rotational speed. The vehicles which are equipped with Mecanum wheels usually have four wheels, which are arranged in a rectangle. With known Mecanum wheel-operated vehicles, the inclined rotary roller axes are arranged on the support plane either star-like to the vehicle middle or the rotary roller axes are located on a circle projection. As mentioned, the rotational speed and the direction of rotation of each Mecanum wheel is to be activated individually, so that through individual direction of rotation selection of the Mecanum wheels relative to the road force, vectors are created which through the moveable rollers form two directions and in sum with the vectors of the other wheels add up to a total movement direction for the vehicle. In the past, attempts to achieve a breakthrough or widely distribute the Mecanum wheel drive were made in vain. Mecanum wheel-operated vehicles were developed for example in the form of conveying vehicles, wheelchairs for mobility impaired persons, transport vehicles or for robotics. The breakthrough of the technology has not been successful so far, presumably since during the rolling of the Mecanum wheels during the change in contact between two rollers which are adjacent in circumferential direction to the surface undefined driving states briefly result, in which the vehicle “floats” or does not follow a desired movement path in a defined manner.
From WO 2011/113562 A2 a Mecanum wheel vehicle is known, the Mecanum wheels of which comprise two rims each which are rotatable about a common driveshaft, wherein the rims for braking purposes are adjustable relative to one another along the common driveshaft axis. In this way, the rims can be adjusted towards one another and the rollers of the one rim braked on the respective other rim. The driving behaviour of the known Mecanum wheel vehicle is not improved through the described measure.